Abstract:
Structural cement panel for resisting transverse and shear loads equal to transverse and shear loads provided by plywood and oriented strain board, when fastened to framing for use in shear walls, flooring and roofing systems. The panels provide reduced thermal transmission compared to other structural cement panels. The panels employ one or more layers of a continuous phase resulting from curing an aqueous mixture of calcium sulfate alpha hemihydrate, hydraulic cement, coated expanded perlite particles filler, optional additional fillers, active pozzolan and lime. The coated perlite has a particle size of 1-500 microns, a median diameter of 20-150 microns, and an effective particle density (specific gravity) of less than 0.50 g/cc. The panels are reinforced with fibers, for example alkali-resistant glass fibers. The preferred panel contains no intentionally added entrained air. A method of improving fire resistance in a building is also disclosed.
Abstract:
A cementitious panel with ballistic and blast resistant properties having a core layer of ultra-high compressive strength composite and at least one skin layer. The panels can also be used in walls, ceiling and flooring panels which require high compressive strength for resistance to earthquakes and surfaces resistant to surface abuse such as in prison and other institutions. The panel core layer has a continuous cementitious phase resulting from the curing of an aqueous mixture, in the absence of silica flour, of inorganic cement binder, inorganic mineral filler having a particle size of about 150-450 microns, a pozzolanic mineral filler, polycarboxylate based superplasticizer, alkanolamine and acid or alkali metal acid salt; and water. The mixture may be uniformly reinforced with fiber added before curing. The cementitious core layer is then reinforced with the skin, such as fiber reinforced polymer, attached to at least one panel surface.
Abstract:
A self-leveling cementitious mixture with excellent flow properties and which hardens with a controlled rate of strength development to an ultra-high compressive strength composite composition for use in making articles such as cementitious armor panel with ballistic and blast resistant properties including: a continuous phase resulting from the curing of an aqueous mixture, in the absence of silica flour, of inorganic cement binder, inorganic mineral filler having a particle size of about 150-450 microns, pozzolanic mineral filler, polycarboxylate based self-leveling agent and water. The cementitious mixture may include alkanolamine, such as thethanolamine, and acid or acid salt, such as tartaric acid. The cementitious composition may be reinforced with reinforcing fibers, e.g. glass fibers, in an amount of about 0.5 - 6.0 % by volume of the overall cementitious composition. The fibers are uniformly dispersed in the cementitious composition before it is cured to form a final cementitious armor panel.
Abstract:
A slurry distribution system can include a feed conduit and a distribution conduit in fluid communication therewith. The feed conduit can include a first feed inlet and a second feed inlet disposed in spaced relationship thereto. The distribution conduit can extend generally along a longitudinal axis and include an entry portion and a distribution outlet in fluid communication therewith. The entry portion is in fluid communication with the first and second feed inlets of the feed conduit. The distribution outlet extends a predetermined distance along a transverse axis, which is substantially perpendicular to the longitudinal axis. The slurry distribution system can be placed in fluid communication with a gypsum slurry mixer adapted to agitate water and calcined gypsum to form an aqueous calcined gypsum slurry.
Abstract:
A method and apparatus for providing an evenly mixed additive enhanced gypsum slurry to a web. Calcined gypsum and water are inserted into a mixer (12) through at least one inlet (26,28) of the mixer (12). The contents are agitated to form a slurry. The slurry is passed from an outlet (34) of the mixer (12) into a conduit (38). An additive is introduced into the slurry along a length of the conduit (38) to achieve a flow stream of a slurry/additive mixture. A cross section (60) of the flow stream is expanded in the conduit (38) while not changing direction of the flow stream and a direction of the flow stream is changed while not expanding the cross section (60) of the flow stream and conduit (38), all prior to the flow steam exiting from an outlet (42) of the conduit.
Abstract:
A slurry distributor (100) for use in a continuous manufacturing process includes an inlet opening (102) and a shaped duct (112) adapted to receive a flow of slurry provided at the inlet opening (102). The shaped duct (112) has a parabolic guide surface adapted to redirect the flow of slurry. An outlet opening (104) in fluid communication with the shaped duct (112) is adapted to discharge the flow of slurry from the slurry distributor (100).
Abstract:
Described herein is a composite board and a method of producing a composite board, the board having increased fire endurance. The board comprises a sheet having a thickness greater than about 0.014 inches, and a thermal conductivity of about 0.1 w/(m.k.) or less. The composite board can be part of a wall assembly comprising two boards defining an interior cavity, the sheet facing the interior cavity.
Abstract:
Disclosed are methods relating to an extruded pregelatinized, partially hydrolyzed starch prepared by mixing at least water, non-pregelatinized starch, and acid to form a starch precursor. The acid can be a weak acid that substantially avoids chelating calcium ions or a strong acid in a small amount. In the method, pregelatinization and acid-modification of the starch precursor occurs in one step in an extruder. Also disclosed are methods of preparing board using the starch prepared according to the methods, as well as starches and boards prepared by various methods of the invention.
Abstract:
A multi-piece mold for use in a method for making a slurry distributor includes a plurality of mold segments adapted to be removably secured together. The mold segments are configured such that, when the mold segments are assembled together, the assembled mold segments define a substantially continuous exterior surface adapted to be a negative image of an interior flow region of a slurry distributor molded thereupon. Each mold segment has a maximum cross-sectional area in a plane substantially transverse to a direction of movement of the mold segment along a removal path out of a respective opening of the molded slurry distributor. The maximum cross-sectional area of each mold segment is up to about 150% of the smallest area of the interior flow region of the molded slurry distributor through which the mold segment traverses when moving along the respective removal path.
Abstract:
Disclosed are product (e.g., panels), slurry, and methods relating to a pregelatinized starch having a mid-range viscosity (i.e., from about 20 centipoise to about 700 centipoise), and an extruded pregelatinized starch.